To help with adding and subtracting fractions.
Use distribution to find the least or greater common factor
Yes.
No.
you use the lcm (least common multiple).
Use one of the usual methods to get the least common multiple. To get additional multiples, multiply this least common multiple by 0, by 1, by 2, by 3, etc.
Use some method which you probably already learned, to find the least common multiple. All the other common multiples are multiples of this least common multiple, so you can multiply the least common multiple by 2, by 3, by 4, etc., to get additional common multiples.
When adding or subtracting unlike fractions, the LCM process is used to find the least common denominator.
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multiples: Least Common Multiple
When adding or subtracting fractions with different denominators their least common multiple must be found in order to carry out the given calculations.
None. The LCM (least common multiple) is the smallest positive whole number exactly divisible by two or more whole numbers.